IntroductionThe antimalarial drug mefloquine (MQ) is associated with neuropsychiatric adverse reactions, some of which may predict the development of more serious effects. Although prescribing guidance in the United States drug label (DL) recommends to discontinue MQ at the onset of neuropsychiatric symptoms, only certain reactions are listed in both the DL and the corresponding patient medication guide with a recommendation to discontinue or to consult a physician should they occur. To identify possible prodromal reactions for which there is complete or partial agreement in prescribing and patient recommendations, a systematic comparison of international drug safety labeling was performed.MethodsThe full text of each DL and medication guide (or equivalent) from six primarily English-speaking countries was reviewed to identify specific reactions with corresponding recommendations in drug safety labeling. Percentage agreement across the countries in corresponding recommendations was determined by MedDRA® high level group term (HLGT).ResultsRecommendations were found for reactions in 22 neuropsychiatric HLGTs. Complete or partial international agreement was found for reactions in 11 (50%) HLGTs.ConclusionThis analysis suggests opportunities for physicians to improve patient counseling and for international drug regulators to clarify language in MQ safety labeling to reflect national risk–benefit considerations.